In a wireless charging system, a wireless power transmitting device such as a device with a charging surface wirelessly transmits power to another electronic device such as a battery-powered, portable electronic device. The portable electronic device receives the wirelessly transmitted power and uses this power to charge an internal battery and to power components in the portable electronic device.
It can be challenging to perform wireless charging operations in a wireless charging system. For example, it can be challenging to ensure that foreign objects such as coins that are present on a charging surface are not inadvertently heated during wireless charging operations.